APC Back-UPS XS XS900 (BX900) 12V 7Ah UPS Battery - This is an AJC Brand Replacement This is an AJC Brand&#174; Replacement for a APC XS900 (BX900) 12V 7Ah UPS Battery Voltage: 12V (12 Volts) Capacity: 7Ah Terminals: F2 Number of Batteries Required for a Full Replacement 2